Pfizer and BioNTech announced on Friday that their Covid vaccine is effective against one of the mutations in the new contagious variants in the UK and South Africa.
Independent experts said the results were good news, but warned that each of these coronavirus variants have several different potentially dangerous mutations that have not yet been studied. So it’s possible that one of these mutations could affect the effectiveness of the vaccine.
“It’s the first step in the right direction,” said Dr. John Brooks, the chief medical officer of the Covid-19 emergency department at the Centers for Disease Control. “I hope the additional work that comes out in the future matches this insight.”
The new variant, known as B.1.1.7, first gave cause for concern in December when British researchers found it was rapidly becoming more common in people with Covid-19. Since then, it has appeared in 45 countries.
Subsequent research has confirmed that it has the ability to spread more easily from person to person. On Friday, Public Health England published a new study on B.1.1.7 in which researchers estimated that the variant is 30 to 50 percent more transmissible than other forms of the virus.
The viral line that leads to B.1.1.7 has accumulated 23 mutations. Of particular concern to scientists are eight mutations that affect the gene for a protein called spike on the surface of coronaviruses. That’s because the viruses use the spike protein to capture human cells. It is possible that one or more of them will help B.1.1.7 enter cells more successfully.
One of these mutations, known as N501Y, is of particular concern. Experiments have shown that it allows the virus to bind more tightly to cells. And it has appeared in other lines of the coronavirus as well, including a variant identified in South Africa in December. This variant, named B.1.351, quickly spread across the country and has so far expanded to a dozen other countries.
In the new study, which went online Thursday and has not yet undergone a formal scientific review, researchers from the University of Texas Medical Department conducted an experiment to see if the Pfizer BioNTech vaccine was against viruses with the N501Y mutation works. They found that in cells in the laboratory, the mutated virus could not infect human cells mixed with antibodies from vaccinated people. The antibodies clung to the coronaviruses, preventing them from entering cells. Despite the N501Y mutation, the experiment showed that the antibodies produced by the vaccine were still able to bind to the viruses.
“This indicates that the key N501Y mutation found in the emerging variants in the UK and South Africa does not create resistance to the immune responses induced by the Pfizer BioNTech vaccine,” the companies said in a press release .